<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        *{
            margin: 0;
            padding: 0;
            list-style: none;
        }
        #app{
            margin: 0 auto;
            margin-top: 50px;
            width: 600px;
        }
    </style>
</head>
<body>
    <div id="app">
        <input v-model="val" type="text">
        <button @click ="addItem">添加</button>
        <div>
            <h2>正在进行的事件{{len}}</h2>
            <ul>
                <li v-for="(item,index) in arr" v-show ="!item.checked">
                    <input v-model ="item.checked" type="checkbox">
                    {{item.val}}
                    <button @click="del(index)">删除</button>
                </li>
            </ul>
            <h2>已经完成的事件{{arr.length - len}}</h2>
            <ul>
                <li v-for="(item,index) in arr" v-show ="item.checked">
                    <input v-model ="item.checked" type="checkbox">
                    {{item.val}}
                    <button @click="del(index)">删除</button>
                </li>
            </ul>
        </div>
    </div>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <script>
        new Vue({
            el:"#app",
            data:{
                val:"",
                arr:[],
            },
            computed:{
                len(){
                    return this.arr.filter((item)=>{
                        return item.checked === false
                    }).length
                }
            },
            methods:{
                addItem(){
                    this.arr.push({
                        val:this.val,
                        checked:false,
                    })
                    this.val=""
                },
                del(index){
                    this.arr.splice(index,1);
                }
            },
        })
    </script>
</body>
</html>